| Siheung-si South Lismore | Eastern Australia Time | -01:00 |
| Siheung-si South Melbourne | Eastern Australia Time | -01:00 |
| Siheung-si South Miami | Eastern Time | 13:00 |
| Siheung-si South Jakarta | Western Indonesia Time | 02:00 |
| Siheung-si South Lancaster | Eastern Time | 13:00 |
| Siheung-si South Kilvington | United Kingdom Time | 08:00 |
| Siheung-si South Kingstown | Eastern Time | 13:00 |
| Siheung-si South Kuta | Central Indonesia Time | 01:00 |
| Siheung-si Zuidhorn | Central European Time | 07:00 |
| Siheung-si Zuidoostbeemster | Central European Time | 07:00 |
| Siheung-si Zugliano | Central European Time | 07:00 |
| Siheung-si Zoutelande | Central European Time | 07:00 |
| Siheung-si Xaxim | Brasilia Time | 12:00 |
| Siheung-si Zürs | Central European Time | 07:00 |
| Siheung-si Wynn Vale | Central Australia Time | -00:30 |
| Siheung-si Wynnewood | Eastern Time | 13:00 |
| Siheung-si Wynyard | Eastern Australia Time | -01:00 |
| Siheung-si Wythall | United Kingdom Time | 08:00 |
| Siheung-si Wytheville | Eastern Time | 13:00 |
| Siheung-si Xaafuun | East Africa Time | 06:00 |
| Siheung-si Xàbia | Central European Time | 07:00 |
| Siheung-si Wyomissing | Eastern Time | 13:00 |
| Siheung-si Wyong | Eastern Australia Time | -01:00 |
| Siheung-si Xalapa | Central Time | 14:00 |
| Siheung-si Xalapa Enríquez | Central Time | 14:00 |
| Siheung-si Xalisco | Mexican Pacific Time | 15:00 |
| Siheung-si Worrigee | Eastern Australia Time | -01:00 |
| Siheung-si Wörrstadt | Central European Time | 07:00 |
| Siheung-si Workum | Central European Time | 07:00 |
| Siheung-si Woody Point | Eastern Australia Time | -01:00 |
| Siheung-si Woolloongabba | Eastern Australia Time | -01:00 |
| Siheung-si Worb | Central European Time | 07:00 |
| Siheung-si Wrightsville | Eastern Time | 13:00 |
| Siheung-si Wrightsville Beach | Eastern Time | 13:00 |
| Siheung-si Woy Woy | Eastern Australia Time | -01:00 |
| Siheung-si Zwingenberg | Central European Time | 07:00 |
| Siheung-si Zwiefalten | Central European Time | 07:00 |
| Siheung-si Zweisimmen | Central European Time | 07:00 |